Electric system



June 21, 1955 Filed March 15, 1944 R. H. RINES ELECTRIC SYSTEM 4Sheets-Sheet l June 21, 1955 H. RINES ELECTRIC SYSTEM 4 Sheets-Sheet 2Filed March 13, 1944 vwrr5 Q/ June 21, 1955 R|NE$ 2,711,534

ELECTRIC SYSTEM Filed Mqrch 13, 1944 4 Sheets-Sheet 3 UJHUH'YWPLWIHW27/21/19/0/1 Ccf June 21, 1955 R. H. RINES 2, 11, 4

ELECTRIC SYSTEM Filed March 13, 1944 4 Sheets-Sheet 4 ELECTRIC SYSTEMRobert Harvey Rines, Brookline, Mass.

Application March 13, 1944, Serial No. 526,269

61 Claims. (Cl. 343-413) The present invention relates to electricsystems, and more particularly to radio-transmitting and radio-receivingsystems that, while having more general fields of usefulness, areespecially adapted for use in television.

An object of the invention is to provide a new and improvedradio-receiving system.

An additional object is to provide a new and improved radio-wave antennasystem useful for reception, transmission or both.

A further object is to provide a novel wave-guiding structure.

An additional object is to provide a novel transmitting scanning antennasystem.

Still another object is to provide a novel receiving scanning antennasystem.

Another object is to provide a new and improved television system.

Another object is to provide a novel combined radioand-televisionsystem.

Another object of the present invention is to provide a new and improveddirection-finding radio-locator system for both detecting the presenceof a body and render ing it visible.

Other and further objects will be explained hereinafter and will beparticularly pointed out in the appended claims.

The invention will now be more fully explained in connection with theaccompanying drawings, in which Fig. l is a simplified diagrammatic viewof circuits and apparatus arranged and constructed in accordance with apreferred embodiment thereof; Fig. 2 is a section taken upon the line2--2 of Fig. 1, looking in the direction of the arrows; Fig. 3 is adiagram representing the scanning of a slot by a scanning guide, at eachof eight positions, with a second slot yet unscanned by a correspondingsecond guide; Fig. 4 is a section taken upon the line 4-4 V of Fig. 2,looking in the direction of the arrows; Figs. 5 to 13 are explanatorydiagrams, drawn to scale in relation to one another, diagrammaticallyillustrating the timing of the operation of the various parts: Fig. 5illustrates a train of eight transmitted pulses, during the time ofscanning of a first slot by a first aperture-guide of thehereinafter-described discs; Fig. 6 illustrates the correspondingreceived echoes; Fig. 7 is a diagrammatic representation of thepositions occupied by the said scanning opening or guide at timescorresponding to the said pulses; Fig. 8 is similar to Fig. 6, exceptthat the received pulses are shown amplified in the electron multiplier;Fig. 9 is representative of the received amplified pulses as applied tothe control electrode of the oscillograph tube; Figs. 10 and 11 arerepresentative of the pulses produced by the horizontal-division and thehorizontalsweep circuits; Figs. 12 and 13 are graphs corresponding toFigs. 10 and 11 for the vertical division and the vertical-sweepcircuits; Fig. 14 is a view of a transmitting device similar to thereceiving device of Fig. 1; and Fig. 15 is a view of a modification.

Let it be assumed that electromagnetic waves which nited States Patent 0ice may be transmitted in pulses are directed toward an object, say, anairplane (not shown), from which they are reflected and scattered towarda receiving station. At the receiving station, the radio waves thusreflected and scattered may be focused by an electromagnetic dielectriclens 5 upon a receiver wave-guide 203. The dielectric lens 5 may bereplaced by a parabola or any other suitable focusing mirror.

The wave-guide 203 is shown provided with discs 207 and 209 havingaperture-guides and slots, respectively. The disc 207 in the wave-guide203 is provided with any desired number of electromagnetic dielectric ormetallic rods or guides 210, 212, 214, 216, 218, 220 and 222, spirallyarranged, somewhat in the manner of a Nipkow disc. The disc 209,disposed in the wave-guide 203 beyond the disc 207, is provided withslots 228, 230, 232, 234, 236, 238 and 240, corresponding in number andposition to the number and the position of the guides in the disc 207,and placed successively below one another.

The guides in the disc 207 protrude from the disc 207 towards thecorresponding slots in the disc 209, as shown in Fig. 4. The discs 207and 209 may be relatively rotatable. The disc 207, for example, may berotated by a motor 48 and the disc 209 may be stationary, as shown. Thedisc 207 is shown rotatable in a groove 206, in order to preventradiation losses, and to this end, the groove may serve as aquarter-wave trap. The guides in the disc 207 will thus successivelyscan the corresponding slots in the disc 209.

During a single rotation of the disc 207 by the motor 48, therefore, allthe slots of the disc 209 will be scanned, in succession, at equallyspaced intervals of time, beginning with the first slot 228, and endingwith the last slot 240, as shown in Fig. 2. Continued rotation of thedisc 207 by the motor 48 will result in successive repetitions of thisscanning process. The disc 209 may, of course, be rotated at a slowerspeed than the disc 207, thus permitting a wider area of scan than if itwere stationary.

Improper phase relations, such as may be caused by the zone-plateeffect, may be prevented in well known ways. The lengths of thedielectric guides protruding from the holes in the disc 207, forexample, may be varied, as illustrated, for producing the proper phaserelations.

Though only a small number of guides and slots is shown in therespective discs, this is merely for illustrative purposes, and in ordernot to confuse the disclosure. It will be understood that, in practice,a large number of guides and slots will be employed.

The slots in the disc 209 will receive diiferent field strengths ofradio energy, corresponding to the amount of energy reflected orscattered from the various parts of the object, such as thebefore-mentioned airplane, and converged upon the disc 209 by the lens5. A radioenergy picture or scene of the said object is thus distributedupon the disc 209. By means of the present invention, this radio-energypicture or scene, limited to the area occupied by the slots in the disc209, may be converted into a visible picture 123. According to thepreferred embodiment of the invention, the visible picture 123 is causedto appear upon the fluorescent screen 106 of a display cathode-rayoscilloscope tube 90. Though the tube is shown operating on theelectrostatic principle, a magnetic-scope deflector or a combination ofmagnetic and electrostatic forces may be employed. The invention thusprovides a means for producing upon the screen 106 images or indicationscorresponding to the radio-frequency energy received by thecorresponding slots and guides of the discs 209 and 207, respectively.

The radio-frequency-energy pulses converged on the slots in the disc 209by the lens 5, and scanned by the small guides 210, 212, 214, 216, 218,220 and 222 of the disc 207 of the radio-wave pick-up device 203, etc.,after transmission through the small guides and through the wave-guide203, are received upon an antenna 202 of preferably fixed or constantpolarization, as shown. The wave-guide 210, for example, couples orabsorbs the converged energy from, and scans, the uppermost elementalpath or region of the radio-wave-energy distribution imaged upon theplane of the disc 209 from a region of space containing the scene, suchas the airplane object beforementioned. For some purposes, of course,the said uppermost elemental path or region may itself be regarded asthe radio-wave image that is thus scanned, though it is not the completeimage of the scene. Similar remarks apply to the physically displacedscanning paths or regions of the other wave-guides 212, 214, 216, 218,220, 222, etc., each of which may be regarded itself as a radiowaveimage. The scanned waves are converted into electrical signals, beingtransmitted to an electron multiplier 24 and a rectifier 26, and fromthere to the control-grid electrode 92 of the vacuum-tube part 88 of theoscilloscope tube 90.

For simplicity, the connections between the antenna 202 and the electronmultiplier 24 are shown as leads whereas, in reality, they may be waveguides or conducting dielectrics or low-loss coaxial lines.

If the scanned waves received in the wave-guide 203 are of the typehaving a horizontal electric vector, the circular path described by theaperture will cause slight variations in intensity transmitted duringthe scanning of each slot. This may be compensated for by insertingvaried attenuating dielectrics along the slots.

The output of the antenna 202 may be superheterodyned in any well-knowncrystal mixer, if desired, or it may be rectified by a crystal rectifierin the guide (Ultra High Frequency Technique, by Brainerd, Koehler,Reich and Woodrufl, pages 486, 487).

Electrons emitted from the cathode 94 of the vacuumtube part 88 of theoscilloscope 90 will become enabled to pass by the grid 92 to the anode96 of the tube 88. The electrons will continue to travel in a streamfrom the anode 96, between a pair of vertically disposed oscilloscopedeflector plates 98 and 100, and between a pair of horizontally disposedoscilloscope deflector plates 102 and 104, to impinge finally on theviewing screen 106 of the oscilloscope 90. A horizontal-sweep-time base,applied to the vertically disposed deflector plates 98 and 100, willcause the electron stream from the cathode 94 to become deflectedhorizontally, and a vertical-sweeptime base, applied to the horizontallydisposed deflector plates 102 and 104, will cause the electron stream tobecome deflected vertically. The plates 98 and 104 are shown grounded.

During the scanning of a particular slot of the disc 209 by a particularguide of the disc 207, the pulse generator 4 triggers ahorizontal-division circuit 63. This division circuit produces one pulsefor every group of input pulses created during the scanning of one slot,and that one pulse, in turn, triggers a horizontal sweep-currentgenerator 263 (see Termans Radio Engineering, page 740; 1937 edition).This causes the electron beam of the cathode ray tube to sweephorizontally across the tube 90, between the vertically disposed plates98 and 100, the electron stream then being quickly returned to itsnormal position. During this horizontal sweep, the grid 92 of the vacuumtube 88 receives varying degrees of energy from intermediate received orpicked-up radioenergy echoes of the transmitted pulses that have beenconverted into electrical signals, causing an intensity gradation alongthe horizontal sweep corresponding to energy received from a horizontalscan .of part of the object. Each spot, along a particular horizontalsweep, will become brightened according to the amount of radio :energyreceivedat the point of its scan by the corresponding guide in the disc207.

cuit 69, which produces one pulse for every complete rotation of thedisc 207, corresponding to every complete picture scan. This triggers avertical sweep circuit 269, causing each successive horizontal sweep,corresponding to each of the substantially parallel radio-wave scanningpaths, to be displaced orthogonally, namely, vertically, in order tooccur below its predecessor, corresponding to the orthogonaldisplacement of the radio-wave scanning paths, until the complete framehas been scanned.

The division circuits 63 and 69 may be unbalanced multivibrators, 'orany other conventional circuit which gives one output pulse to every somany input pulses (see Reich: Theory and Application of Electron Tubes,pages 359 to 361, 1939 edition, or Termans Radio Engineering, page 374,1937 edition).

The definition depends upon the number of transmitted and receivedpulses corresponding to the scanning of each slot. The more of these,the less the range, naturally, that the object can be televised. This isbecause the range is chiefly determined by the interval between pulses;

'that is, by the time allowed for the echo to return. The

definition depends also on the number of slots to be scanned as well ason their dimensions. The apertureguides in the disc 207 and the slots inthe disc 209 should, of course, be of suflicient size to be consistentwith the well-known wave-guide conditions; namely, the guides should beof transverse cross-sectional configuration sufficient to permit thepropagation therethrough of electromagnetic radio waves above a criticalfrequency related to the said transverse cross-sectional configuration,as otherwise, electromagnetic energy of the proper frequency will notpass therethrough.

As an illustration, let it be assumed that there are 100 apertures inthe disc 207 and, correspondingly, 100 slots in the disc 209. Let it befurther assumed that the electromagnetic pulses are of one microsecondduration. Let it be assumed also that the range to be covered is ten totwelve miles, or 15,000 meters. This corresponds to a time distance 1000m g XTO-S 50 microseconds The pulse-recurrence frequency is thereciprocal of this, or 20,000 per second.

If it be assumed that, during the exposure of each hole, eight pulsespass, then 50 8=400 microseconds per hole (omitting pulse duration,which is relatively negligible). For 100 holes, this would be 0.04seconds per complete scan, or one frame every four-hundredths of asecond, which is above the flicker limit of the eye. This corresponds toa rotation of the motor 48 at 25 cycles per second, or 1500 revolutionsper minute.

Transmitted pulses of one microsecond duration and 20,000 cycles persecond recurrence frequency are diagrammatically represented by Fig. 5.A train of eight such pulses 71 is shown, representing the energytransmitted during the time that the first aperture-guide 210 of thedisc 207 scans the first slot 228 in the disc 209. Successive moments ofthe scan are represented in Fig. 7 as positions 1 to 8 of the openingalong the slot 228, as illustrated in Fig. 3. After eight transmittedpulses have occurred, the opening 210 has completely scanned :the slot228, and the opening 212 is starting to scan the 7 5 210,. Thesereceived-pulses, in Fig. 6,-represent the-energy returning from variousportions of the object along that scan.

Fig. 8 represents these received pulses as amplified pulses 77 in theelectron multiplier 24. These are then rectified by the rectifier 26,and the rectified pulses 79, as illustrated in Fig. 9, are fed betweenthe control-grid 92 and the cathode 94 of the cathode-ray tube 90.

Fig. shows the single pulse 81 produced once to every eight transmitterpulses by the horizontal-division circuit 63, as previously described.This triggers the saw-tooth generator 263, causing it to produce ahorizontal-sweep voltage 83, shown in Fig. 11, which is applied to thevertically disposed horizontal deflector plate 100. This causes theelectron stream to sweep across the screen 106, and the pulses of Fig. 9modulate the intensity of the sweep at successive portions thereof,according to the respective strength of radio energy from the object.

Fig. 12 shows the output of the vertical-division circuit 69, whichproduces one pulse 85 corresponding to every complete scan of the disc209. This, in turn, triggers the vertical-sweep circuit 269, which givesthe wave form 87 of Fig. 13 on the vertical deflection plate 102. Thiscauses successive horizontal sweeps to appear at successive lowerpositions on the screen 106, until the complete scan is accomplished,when a repetition process is effected.

The horizontal dotted lines 89, 91, 93, 95, 97, 99 and 101 have the samesignificance, in Figs. 6 and 8 to 13, respectively, that the line 73 hasin Fig. 5.

The pulse generator 4 may comprise a crystal or other stable oscillatoras a source of steady alternating-current voltage to feed the horizontaland vertical division and sweep circuits with synchronizing pulses,thereby to obtain and maintain the said synchronized relationshipbetween the motor 48 and the sweep circuits.

While, for illustrative purposes, the scanning antenna system of thepresent invention has been described in connection with the reception ofradio waves and the production of a likeness or indication correspondingto the received radio-wave distribution, it may similarly be used as atransmitting antenna with or without a focusing device, depending uponthe desired result. In Fig. 14, for example, a transmitting antenna 3 isshown corresponding to the receiving antenna 203 of Fig. 1, similarparts being given similar reference numerals with the prefix 200omitted. It is to be understood that the previous description of theoperation and possible modification of the receiving scanning antenna203 applies equally to the transmitting scanning antenna 3. The antenna2 is connected to a transmitter such as a radio-frequency pulsegenerator 4'. When both the disc 7 carrying the guides 10, 12, 14, 16,18, 20, 22, etc. and the disc 9 having the wave-guiding apertures,openings or slots 28, 30, 32, 34, 36, 38, 40, etc. are rotated, asbefore described in connection with a modified operation of Fig. 1, anarrow directivity pattern or pencil of radiation is caused to bedirected through angles subtending two dimensions of a scene to bescanned, namely, perpendicular radial and circumferential dimensions.

In fact, a unit such as 3, 7, 9, etc. or 203, 207, 209, etc. can alsoserve, if desired, as a common transmitterand-receiver as shown at 111in Fig. 15, if, after transmission, the antenna is connected to thereceiving apparatus, and after reception, back to the transmittingcircuit, by any well-known switching device such as relays or sparkgaps.

It has been stated that the dielectric lens 5 may be replaced by aparabola or any other suitable ray-direction-changing focusing mirror. Aparabola 103, for focusing or collimating the radio image on a commontransmitting-and-receiving scanner 111, as before described, isillustrated in Fig. 15, the axis of the reflector 103 being shown inline with the center of the scanner 111, and the plane of the front faceof the scanner 111 being substantially perpendicular to the said axis.The transmitted pulses are caused to travel from the transmittingchannel 105, shown as a circular wave-guide, which is connected by aswitching mechanism 107, as mentioned previously, to wave-guide 109. Thewaveguide 109 transmits the pulses to the combinationtransmitting-and-receiving wave-guide 111, which corresponds to thewave-guide system 3, 7, 9, etc. of Fig. 14. After scattering andreflection from, for example, the airplane object, the reflected andscattered rays will be returned to the combinationtransmitting-and-receiving waveguide 111, whereupon they will be guidedback along the guide 109 to a receiving wave-guide 113 for visual orother presentation. The scanning energy-coupling or energy-absorbingguides of the device 111, corresponding to the guides 10, 12, 14, etc.or the guides 210, 212, 214, etc. of respective Figs. 14 and 1, willdescribe circular paths or regions displaced from one another andsurrounding the focal point along the axis of the reflector 103 as acenter, illustrated by the merging ray lines at F on the front face ofthe scanner 111 of Fig. 15.

The wave-guides of the present invention, furthermore, may be conical,rectangular or any other desired shape, though circular may be the mostconvenient, the broad underlying concept of the invention clearly notbeing dependent upon the particular illustrated shape or configurationof the guides or slots. The electromagnetic radio waves employed,moreover, are preferably in the ultra-high-frequency microwave range,say of 3 or 1.5 centimeters wavelength, and may be of the continuouswavetype or of any other type of modulated wave, though pulsed energy,before described, at present has the advantage of economical and easyhigh-power ultrahigh-frequency generation.

Further modifications will occur to persons skilled in the art, and allsuch are considered to fall within the spirit and scope of theinvention, as defined in the appended claims.

What is claimed is:

1. An electric system having, in combination, means for receivingmicrowave radio waves from an object, a plurality of microwavetransmitting means, means provided with a plurality of openings, onecorresponding to each microwave transmitting means, means for relativelymoving the microwave transmitting means and the openings-provided meansto enable the radio waves to pass through the openings and thecorresponding microwave transmitting means in succession, thereby toscan a region of space traversed by the radio waves, and means fortransmitting the scanned radio waves to the microwave receiving means.

2. An electric system having, in combination, a plurality of microwavetransmitting means, means providing a plurality of openings, onecorresponding to each microwave transmitting means, means for causingmicrowave radio waves from an object to produce a radioenergy image ofthe object, and means for relatively moving the microwave transmittingmeans and the openings to scan the image to cause each transmittingmeans to scan only the corresponding opening.

3. An electric system having, in combination, a plurality of microwavewave-guide means of the type having a transverse cross-sectionalconfiguration to permit the propagation therethrough of microwave radiowaves above a critical frequency related to the said transversecross-sectional configuration, the wave-guide means being adapted to bepositioned for the transmission therethrough of radio waves from anobject of microwave frequency above the critical frequency, means forcausing the wave-guide means to scan the radio waves from the object,and means for receiving the microwave radio waves after transmissionthrough the wave-guide means.

4. An electric system having, in combination, a plurality of microwavewave-guide means of the type having a transverse cross-sectionalconfiguration to permit the propagation therethrough of microwave radiowaves above a critical frequency related to the said transversecross-sectional configuration, means comprising the plurality ofwave-guide means for successively scanning a region of space traversedby radio waves from an object of a frequency above the criticalfrequency along two orthogonal directions in substantially parallelpaths, and means for receiving the scanned radio waves.

5. An electric system having, in combination, a plurality of microwavewave-guide elements of the type having a transverse cross-sectionalconfiguration to permit the propagation therethrough of microwave radiowaves above a critical frequency related to the said transversecross-sectional configuration, and means for operating the microwavewave-guide elements successively to cause them to scan successivelydiiferent portions of a region of space traversed by radio waves of amicrowave frequency above the critical frequency.

6. An electric system having, in combination, a plurality of microwavewave-guide elements of the type having a transverse cross-sectionalconfiguration to permit the propagation therethrough of microwave radiowaves above a critical frequency related to the said transversecross-sectional configuration, means for operating the microwavewave-guide elements successively to cause them to scan successivelydifferent portions of a region of space traversed by radio waves of amicrowave frequency above the critical frequency, and microwave meansfor receiving the scanned radio waves.

7. An electric system having, in combination, a micro wave wave guideand a plurality of microwave wave-guide elements of the type having atransverse cross-sectional configuration to permit the propagationtherethrough of microwave radio waves above a critical frequency relatedto the said transverse cross-sectional configuration, and meanscomprising the microwave wave-guide elements for scanning a region ofspace traversed by radio waves of a microwave frequency above thecritical frequency and for directing these canned radio waves to themicrowave wave guide for transmission through the microwave wave guide.

8. An electric system having, in combination, a microwave wave guide anda plurality of microwave waveguide elements of the type having atransverse cross-seetional configuration to permit the propagationtherethrough of microwave radio waves above a critical frequency relatedto the said transverse cross-sectional configuration, means foroperating the microwave wave-guide elements successively to scan aregion of space traversed by radio waves of a microwave frequencyabove-the critical frequency, the microwave wave guide being positionedfor the transmission therethrough of the scanned radio waves, andmicrowave means for receiving the scanned radio waves after transmissionthrough the microwave wave guide.

9. An electric system having, in combination, a plurality of microwavewave guides of the type having a transverse cross-sectionalconfiguration to permit the propagation therethrough of microwave radiowaves above a critical frequency related to the said transversecrosssectional configuration, means disposed near the plurality of waveguides and cooperative therewith providing a plurality of openings, onecorresponding to each microwave wave guide, and means for relativelymoving the microwave wave guides and the openings-provided means.

10. An electric system having, in combination, a -wave guide and aplurality of wave-guide elements of the type having a transversecross-sectional configuration to permit the propagation therethrough ofradio waves above a critical frequency related to the said transversecrosssectional configuration, means for operating the waveguide elementssuccessively to scan a region of space traversed by radio waves from anobject of a frequency above the-critical frequency, the wave guide beingpositioned for the transmission therethrough of the scanned radio waves,means for receiving the scanned radio waves after transmission throughthe wave guide, and means controlled in accordance with the scannedradio waves received by the receiving means for producing an indicationof the object.

11. An electric system having, in combination, a plurality of microwavewave guides of the type having a transverse cross-sectionalconfiguration to permit the propagation therethrough of microwave radiowaves above a critical frequency related to the said transversecrosssectional configuration, means providing a plurality of openings,one corresponding to each microwave wave guide, means for relativelymoving the microwave wave guides and the openings-providing means toenable radio waves from an object of a microwave frequency above thecritical frequency to pass through the openings and the correspondingmicrowave wave guides in succession, thereby to scan a region of spacetraversed by the radio waves, microwave means for receiving the scannedradio waves, and means controlled in accordance with the scanned radioWaves received by the microwave receiving means for producing anindication of the object.

12. An electric system having, in combination, a wave guide and aplurality of wave-guide elements of the type having a transversecross-sectional configuration to permit the propagation therethrough ofradio waves above a critical frequency related to the said transversecrosssection configuration, means for operating the wave-guide elementssuccessively to scan successive portions of a region of space traversedby radio waves from an object of a frequency above the criticalfrequency, the wave guide being positioned for the transmissiontherethrough of the scanned radio waves, means for receiving the scannedradio waves after transmission through the wave guide, an oscilloscopehaving a screen and means for producing an electron stream impinging onthe screen, means for causing the electron stream to scan the screen insynchronism with the scanning of the radio waves by the successivelyoperating wave-guide elements, and means controlled in accordance withthe scanned radio waves received by the receiving means for controllingthe electron stream during its scanning of the screen to produce alikeness of the object on the screen.

13. An electric system having, in combination, microwave wave-guidemeans of the type having a transverse cross-sectional configuration topermit the propagation therethrough of microwave radio waves above acritical frequency related to the said transverse cross-sectionalconfiguration, means for converging radio waves from an object of amicrowave frequency above the critical frequency to produce aradio-energy image of the object, and means comprising the microwaveWave-guide means for scanning the image.

14. An electric system having, in combination, microwave wave-guidemeans of the type having a transverse cross-sectional configuration topermit the propagation therethrough of microwave radio waves above acritical frequency related to the said transverse cross-sectionalconfiguration, means for converging radio waves from an object .of amicrowave frequency above the critical frequency to produce aradio-energy image of the object, means comprising the microwaveWave-guide means for scanning the image and for transmitting the scannedradio waves, and microwave means for receiving the scanned radio wavesafter transmission.

15. An electric system having, in combination, a plurality of microwavewave guides of the type having a transverse cross-sectionalconfiguration to permit the propagation therethrough of microwave radiowaves above a critical frequency related to the said transversecrosssectional configuration, means for causing radio waves from anobject of a microwave frequency above the critical frequency to producea radio-wave image of the object, means for moving the microwave waveguides to scan the image, and means for confining the radio Waves of theradio-wave image to particular scanning microwave wave guides during thescanning.

16. An electric system having, in combination, microwave wave-guidemeans of the type having a transverse cross-sectional configuration topermit the propagation therethrough of microwave radio waves above acritical frequency related to the said transverse cross-sectionalconfiguration, means for converging radio waves from an object of amicrowave frequency above the critical frequency to produce a radio-waveimage of the object, means comprising the microwave wave-guide means forscanning the image and for transmitting the scanned radio waves,microwave means for receiving the scanned radio waves aftertransmission, an oscilloscope having a screen and means for producing anelectron stream impinging on the screen, means for initiating thescanning of the electron stream in synchronism with the scanning of theradio waves by the wave-guide means, and means controlled in accordancewith the scanned radio waves received by the receiving means forcontrolling the electron stream during its scanning of the screen toproduce a likeness of the object on the screen.

17. An electric system having, in combination, microwave waveguide meansof the type having a transverse cross-sectional configuration to permitthe propagation therethrough of microwave radio waves above a criticalfrequency related to the said transverse cross-sectional configuration,means for converging radio waves from an object of a microwave frequencyabove the critical frequency to produce a radio-energy image of theobject, means for scanning the image and for directing the scanned Wavesto the microwave wave-guide means for transmission through thewave-guide means, and microwave means for receiving the scanned radiowaves after transmission through the wave-guide means.

18. An electric system having, in combination, microwave wave-guidemeans of the type having a transverse cross-sectional configuration topermit the propagation therethrough of microwave radio waves above acritical frequency related to the said transverse cross-sectionalconfiguration, means for converging radio waves from an object of amicrowave frequency above the critical frequency to produce aradio-energy image of the object, means comprising the microwavewave-guide means for scanning the image, microwave means for receivingthe scanned radio waves, and means controlled in accordance with thescanned radio waves received by the receiving means for producing alikeness of the object.

19. An electric system having, in combination, waveguide means of thetype having a transverse cross-sectional configuration to permit thepropagation therethrough of radio waves above a critical frequencyrelated to the said transverse cross-sectional configuration, means forconverging radio waves from an object of a' frequency above the criticalfrequency to produce a radio-energy image of the object, means forscanning the radio-energy image, means for directing the scanned radiowaves to the wave-guide means for transmission through the wave-guidemeans, means for receiving the scanned radio waves after transmissionthrough the waveguide means, an oscilloscope having a screen and meansfor producing an electron stream impinging on the screen, means forinitiating the electron stream scanning of the screen in synchronismwith the scanning of the radio waves by the wave-guide means, and meanscontrolled in accordance with the scanned radio waves received by thereceiving means for controlling the electron stream to produce alikeness of the object on the screen.

20. An electric system having, in combination, a plurality of microwaveguides of the type having a transverse cross-sectional configuration topermit the propagation theretl rough of microwave radio waves above acritical frequency related to the said transverse crosssectionalconfiguration, means providing a plurality of openings, onecorresponding to each microwave wave guide, means for causing radiowaves from an object of a microwave frequency above the criticalfrequency to produce a radio-wave image of the object, means forrelatively moving the microwave wave guides and the openings-providedmeans to scan the image, and means controlled in accordance with thescanning for providing a likeness of the object.

21. An electric system having, in combination, a plurality of spirallydisposed wave guides of the type having a transverse cross-sectionalconfiguration to permit the propagation therethrough of radio wavesabove a critical frequency related to the said transversecross-sectional configuration, means for operating the wave guidessuccessively to cause them to scan successively different portions of aregion of space traversed by radio waves of a frequency above thecritical frequency, and means for receiving the scanned radio waves.

22. An electric system having, in combination, a plurality of helicallydisposed wave guides of the type having a transverse cross-sectionalconfiguration to permit the propagation therethrough of radio wavesabove a critical frequency related to the said transverse crosssectionalconfiguration, means for causing radio waves from an object of afrequency above the critical frequency to produce a radio-wave image ofthe object, and means for moving the wave guides to scan the image.

23. An electric system having, in combination, a plurality of microwavewave-guide elements of the type having a transverse cross-sectionalconfiguration to permit the propagation therethrough of microwave radiowaves above a critical frequency related to the said trans versecross-sectional configuration, means for converging radio waves from anobject of a microwave frequency above the critical frequency to producea radio-wave image of the object, means providing a plurality ofopenings, one corresponding to each microwave Wave-guide element, meansfor relatively moving the microwave wave-guide elements and theopenings-provided means to cause the microwave wave-guide elements toscan the corresponding openings, thereby to scan the image, and meansfor receiving the scanned radio waves.

24. In combination, means for imaging radio waves from a scene, a radiowave pick-up device comprising a wave guide, and means for scanning thesaid radio wave image by said pick-up device and converting the energythus picked up into an electrical signal.

- Wave guide having an open end positioned to receive energy from saidimage and having the other end mounted on and terminating in a rotatablewave guide joint, and means for scanning the said radio wave image bysaid pick-up device and converting the energy thus picked up into anelectrical signal.

26. In combination, means for imaging radio waves from a scene, aradio-wave pick-up device comprising wave-guide means, means forscanning an area successive portions of which correspond to successiveportions of the radio-wave image, and means controlled in accordancewith the scanning for converting the energy picked up by the pick-updevice from the different portions of the image into correspondingelectrical signals.

27. In combination, means for imaging radio waves from a scene to bereproduced, a radio-wave pick-up device comprising wave-guide means,means for scanning an area successive portions of which correspond tosuccessive portions of the radio-Wave image, means controlled inaccordance with the scanning for converting the energy picked up by thepick-up device from the different portions of the image intocorresponding electrical signals, an image-reproducing means, means forinitiating the operation of the image-reproducing means in synchronismwith the scanning, and means for supplying the signals to theimage-reproducing means, whereby a picture of the scene is obtained.

28. In combination, means for imaging radio waves from a scene, aradio-wave pick-up device comprising wave-guide means open-ended toreceive energy from the radio-wave image and mounted on and terminatedin a rotatable wave-guide joint, means for scanning an area successiveportions of which correspond to successive portions of the radio-waveimage, and means controlled in accordance with the scanning forconverting the energy picked up by the pick-up device from the differentportions of the image into corresponding electrical signals.

29. In combination, means for imaging radio waves from a scene, aradio-wave pick-up device comprising a plurality of wave guides havingopen ends positioned to receive energy from the image and having endsmount ed on and terminating in a rotatable wave-guide joint, means forscanning the radio-wave image by the plurality of wave guides of thepick-up device, and means for converting the energy thus picked up intoelectrical signals.

30. In combination, means for imaging radio waves from a scene to bereproduced, a radio-Wave pick-up device comprising wave-guide meansopen-ended to receive energy from the image and mounted on andterminating in a rotatable wave-guide joint, means for scanning theradio-wave image by the pick-up device, means for converting the energythus picked up into electrical signals, an image-reproducing means,means for initiating the operation of the image-reproducing means insynchronism with the scanning, and means for supplying the signals tothe image-reproducing means, whereby a picture of the scene is obtained.

31. In combination, means for imaging radio waves from an object, aradio wave pick-up device comprising a wave guide, and means forscanning the said radio.

wave image by said pick-up device and converting the energy thus pickedup into an electrical signal.

32. In combination, means for imaging radio waves from an object, aradio wave pick-up device comprising a wave guide having an open endpositioned to receive energy from said image and having the other endmounted on and terminating in a rotatable wave guide joint, means forscanning the said radio wave image by said pick-up device and convertingthe energy thus picked up into an electrical signal, an imagereproducing means, and means for supplying said signal to saidreproducing means whereby an indication of said object is obtained.

33. In combination, means for imaging radio waves from part of a scene,a radio wave pick-up device comprising wave-guide means having crystaldetector means, and means for scanning the said radio wave image by saidwave-guide means and converting the energy thus picked up and detectedby the crystal detector means into an electrical signal.

34. An electric system having, in combination, Waveguide means of thetype having a transverse crosssectional configuration to permit thepropagation therethrough of radio waves above a critical frequencyrelated to the said transverse cross-sectional configuration, scanningmeans comprising the wave-guide means, means for operating the scanningmeans to cause it to scan only a limited region of space occupied by anobject, such as an airplane, traversed by radio waves from the object ofa frequency above the critical frequency, means for receiving thescanned radio waves, and means controlled in accordance with the scannedradio Waves received by the receiving means for producing an indicationof the object.

35. An electric system having, in combination, waveguide means of thetype having a transverse crosssectional configuration to permit thepropagation therethrough of radio waves above a critical frequencyrelated to the said transverse cross-sectional configuration,

scanning means comprising the wave-guide means, means for operating thescanning means to cause it to scan only a limited region of spaceoccupied by an object, such as an airplane, traversed by radio wavesfrom the object of a frequency above the critical frequency, means forreceiving the scanned radio waves, and cathode-raytube means controlledin accordance with the scanned radio waves received by the receivingmeans for producing an indication of the object.

36. Radiant energy direction-finding apparatus comprising a paraboloidreflector, a first energy-absorbing unit, means for directing said unitin a closed-curve path, the center of said closed-curve pathsubstantially coinciding with the focal point of said reflector, afurther energy-absorbing unit, and means for directing said further unitin a further closed-curve path, both of said units being positioned tocooperate with said reflector, said closed-curve paths being physicallydisplaced from one another.

37. Radiant energy direction-finding apparatus comprising means havingan axis for changing the direction of rays of electromagnetic energywaves, first and second electromagnetic energy couplingunits positionedto cooperate with said ray direction changing means, means for directingsaid first coupling unit in a first path, said first path surroundingsaid axis, and means for directing said second coupling unit in a secondpath, said first and second paths being physically displaced, saidapparatus when employed for radiating radiant energy being effective formaintaining the plane of polarization of said radiant energysubstantially constant.

38. Ultra high frequency direction-finding apparatus comprising meanshaving an axis for collimating electromagnetic energy, a plurality ofelectromagnetic coupling units positioned to cooperate with saidcollimating means, and means for directing said units in differentpaths, the center of the area of one of said paths substantially lyingalong said axis.

39. Apparatus as in claim 38 wherein all of said paths are substantiallydisposed in a plane perpendicularly oriented relative to said axis.

- 40. Apparatus as in claim 39 wherein each of said coupling meansincludes the mouth of a wave-guide.

41. Wave-energy direction-finding apparatus comprising a directivereflector having the form of a paraboloid of revolution, threeenergy-absorbing units, and means for causing said units to traverseseparate circular paths, all of said paths substantially lying in aplane disposed at right angles to the axis of said antenna.

42. Apparatus as in claim 41 wherein at least one of said paths has acenter substantially positioned along the axis of said reflector.

43. An electric system for transmitting or receiving radio-frequencyenergy having, in combination, means for feeding the radio-frequencyenergy along a plurality of paths of different length to a plurality ofwave-guide elements normally ineffective to cooperate with space, thewave-guide elements being of difierent lengths such as to compensate forthe difierences in path-length of the feed thereto, and means forrendering the successive wave guides of the plurality of wave guidessuccessively effective to propagate the radio-frequency energy to orfrom space.

44. An electric system for transmitting or receiving radio-frequencyenergy having, in combination, slot means for transmitting or receivingthe radio-frequency energy, attenuating dielectric material disposedalong the slot means, and wave-guide means for scanning the slot meansto transmit or to receive the radio-frequency energy through thesuccessively disposed portions of the attenuating dielectric materialalong the slot means.

45. An electric system having, in combination, a plurality ofwave-transmitting means, means providing a plurality of openings, onecorresponding to each wavetransmitting means, and means for relativelymoving .the

13 wave-transmitting means and the openings-provided means to cause eachWave-transmitting means to scan only its corresponding opening.

46. An electric system having, in combination, a plurality of waveguides of the type having a transverse cross-sectional configuration topermit the propagation therethrough of radio waves above a criticalfrequency related to the said transverse cross-sectional configuration,means providing a plurality of openings, one corresponding to each waveguide, and means for relatively moving the wave guides and theopenings-provided means.

47. In a radio-wave transmitter or receiver system, an antenna systemcomprising a plurality of slot means for transmitting radio waves fromthe transmitter or receiving and feeding radio waves to the receiver,each of the slot means extending along a first dimension and beingdisplaced along a second dimension from the other slot means, and meansfor successively transmitting radio waves from the transmitter orsuccessively receiving and feeding radio waves to the receiver atsuccessively disposed portions along the first dimension of eachsuccessive slot means displaced along the second dimension insuccession.

48. A radio scanning system including, in combination, wave-guidingmeans for forming a narrow directivity pattern of radio-wave energy,means for scanning said directivity pattern through an angle subtendingone dimension of a scene to be viewed, supplementary means including acontinuously rotatable element interposed between said wave-guidingmeans and said scene for scanning said directivity pattern of radio-waveenergy through an angle subtending another dimension of said scene, anda radio-wave focusing device for focusing the scanning radio-wave energydirectivity pattern.

49. An electric system having, in combination, a wave guide of the typehaving a transverse cross-sectional configuration to permit the passagetherethrough of radio waves above a critical frequency related to thesaid transverse cross-sectional configuration and provided with slotmeans of dimensions sufiicient to pass the said radio waves, meansdisposed in closely fitting relation to the wave guide and havingaperture means, and means for relatively moving the wave guide and theclosely disposed means to align the slot means with the aperture meansin order to permit the passage of radio waves therethrough.

50, An electric system having, in combination, a wave guide of the typehaving a transverse cross-sectional configuration to permit the passagetherethrough of radio waves above a critical frequency related to thesaid transverse cross-sectional configuration provided with an openingfor permitting the passage of the said radio waves between the exteriorand interior of the wave guide through the opening, means disposedadjacent the opening and provided with aperture means, and means forrelatively moving the opening and the apertureprovided means to alignthe aperture and opening means in order to permit the passage of radiowaves therethrough.

51. An electromagnetic system for scanning an object that comprisesmeans for focusing radio waves of predetermined frequency from theobject to form a radiowave distribution corresponding to different partsof the object, wave-guide means of the type having a transversecross-sectional configuration to permit the passage therethrough ofradio Waves above a critical frequency related to the said transversecross-sectional configuration substantially equal to or less than thesaid predetermined frequency for scanning the radio-wave distributionalong one dimension, and further radio-Wave-guiding means for scanningthe radio-wave distribution along another dimension.

52. An electromagnetic system for scanning an object that comprisesmeans for focusing radio waves of predetermined frequency from theobject to form a radiowave distribution corresponding to different partsof the object, wave-guide means of the type having a transversecross-sectional configuration to permit the passage therethrough ofradio waves above a critical frequency related to the said transversecross-sectional configuration substantially equal to or less than thesaid predetermined frequency for scanning the radio-wave distributionalong one dimension, and further radio-wave-guiding means for scanningthe radio-wave distribution along another dimension disposed at rightangles to the said one dimension.

53. An electromagnetic system for scanning an object that comprisesmeans for focusing radio waves of predetermined frequency from theobject to form a radiowave distribution corresponding to different partsof the object, wave-guide means of the type having a transversecross-sectional configuration to permit the passage therethrough ofradio waves above a critical frequency related to the said transversecross-sectional configuration substantially equal to or less than thesaid predetermined frequency for scanning the radio-wave distributionalong one dimenson, and further radiowaveguiding means operable duringthe scanning along the said one dimension for scanning the radio-wavedistribution along another dimension.

54. An electromagnetic system for scanning an object that comprisesmeans for focusing radio waves of predetermined frequency from theobject to form a radiowave distribution corresponding to different partsof the object, wave-guide means of the type having a transversecross-sectional configuration to permit the passage therethrough ofradio waves above a critical frequency related to the said transversecross-sectional configuration substantially equal to or less than thesaid predetermined frequency for scanning the radio-wave distributionalong one dimension, and further radio-waveguiding means operable duringthe scanning along the said one dimension for scanning the radio-wavedistribution along another dimension disposed at right angles to thesaid one dimension.

55. An electromagnetic system for scanning an object that comprisesmeans for focusing radio waves of predetermined frequency from theobject to form a radio-wave distribution corresponding to differentparts of the object, wave-guide means of the type having a transversecrosssectional configuration to permit the passage therethrough of radioWaves above a critical frequency related to the said transversecross-sectional configuration substantially equal to or less than thesaid predetermined frequency for scanning the radio-wave distributionalong one dimension, and further radio-Wave-guiding means interposedbetween the object and the scanning means for scanning the radiowavedistribution along another dimension.

56. An electromagnetic system for scanning an object that comprisesmeans for focusing radio Waves of predetermined frequency from theobject to form a radiowave distribution corresponding to different partsof the object, wave-guide means of the type having a transversecross-sectional configuration to permit the passage therethrough ofradio waves above a critical frequency related to the said transversecross-sectional configuration substantially equal to or less than thesaid predetermined frequency for scanning the radio-wave distributionalong one dimension, and further radio-wave-guiding means interposedbetween the object and the scanning means and operable during thescanning along the said one dimension for scanning the radio-wavedistribution along another dimension.

57. An electromagnetic system for scanning an object that comprisesmeans for focusing radio waves of predetermined frequency from theobject to form a radio-wave distribution corresponding to differentparts of the object, wave-guide means of the type having a transversecrosssectional configuration to permit the passage therethrough of radiowaves above a critical frequency related to the said transversecross-sectional configuration substantially equal to or less than thesaid predetermined frequency for scanning the radio-wave distributionalong one dimension, and further radio-wave-guiding means interposedbetween the object and the scanning means and operable during thescanning along the said one dimension for scanning the radio-wavedistribution along another dimension disposed at right angles to thesaid one dimension.

58. A radio vision scanning system including in combination, waveguiding means for forming a narrow direc tivity pattern of radio waveenergy, means for directing said directivity pattern through an anglesubtending one dimension of a scene to be viewed, and supplementarymeans including a continuously rotatable element interposed between saidwave guiding means and said scene for directing said narrow directivitypatern of radio wave energy through .an angle subtending anotherdimension of said scene.

59. A radio vision scanning system including in combination, waveguiding means for forming a narrow directivity pattern of radio waveenergy, means for directing said directivity pattern through an anglesubtending one dimension of a scene to be viewed, and supplementarymeans including a continuously rotatable element interposed between saidwave guiding means and said scene for directing said narrow directivitypattern of radio Wave energy through an angle subtending adimensiondisposed at right angles to the first mentioned dimension.

60. A radio vision scanning system including in combination, waveguiding means for forming a narrow directivity pattern of radio waveenergy, means for directing said directivity pattern through an anglesubtending one dimension of a scene to be viewed, and supplementarymeans interposed between said wave guiding means and said scene fordirecting said narrow directivity pattern of radio wave energy throughan angle subtending another dimension of said scene.

61. A radio vision scanningsystem including in combination, wave guidingmeans for forming a narrow directivity pattern of radio wave energy,means for directing said directivity pattern through an angle subtendingone dimension of a sceneto be viewed, and supplementary means interposedbetween said wave guiding means and said scene for directing said narrowdirectivity pattern of radio wave energy through an angle subtending adimension disposed at right angles to the first mentioned dimension.

References Cited in the file of this patent UNITED STATES PATENTS ItalyMar. 15, 1936

